At present, there is a problem of cleaning windows and walls of tall buildings. The work is expensive, labor-intensive and may be hazardous. The weather has to be considered as well. When there are strong winds, such work may be still more difficult.
Sometimes a scaffolding has to be erected.
An irregular-shaped building may be still more difficult to clean.
A working platform may be located external to the building and in close proximity thereto. The platform may be moved vertically and horizontally, to gain access to all the windows and places to be cleaned there.
Still, there remains the problem of suitable automatic means for doing the cleaning work itself—the present invention is concerned with replacing manual labor with a remotely controlled system.
The task is not simple: Windows may have protuberances located in their upper part or the lower part, etc. Access may be difficult.
Usually, in tall buildings the windows/walls structure pertains to one of the following types:
A. The window may have a frame which is flat or vertical, of a size of about 0 to 5 cm, in some instances possibly more.
B. Other windows may have flat vertical frames of about 2 to 5 cm, and horizontal frames (window-sill or ledge) which protrude out of the window plane by about 3 cm, and of a width of about 2 to 5 cm.
Balustrades or horizontal frames may protrude out up to 30 cm off the surface of the window or wall.
In walls having a large window (picture window) the structure of the windows frame is usually of the type A or B.
Preferably, the platform with the cleaning means thereon will be moved vertically at a constant rate during the cleaning process. Buildings, however, usually have horizontal ledges or other protuberances which may interfere with the continuous operation of the cleaning means.